Association of hemoglobin-to-red blood cell distribution width ratio and 1-year mortality in patients undergoing transcatheter aortic valve replacement: a retrospective cohort study

Background The association between the hemoglobin-to-red cell distribution width (RDW) ratio (HRR) and mortality in patients undergoing transcatheter aortic valve replacement (TAVR) remains uncertain. This research focuses on exploring the association between HRR and mortality in these patients. Methods The data came from the MIMIC-IV database in the intensive care medical information market. The primary outcome was all-cause mortality within 1 year after TAVR. HRR was calculated as hemoglobin (Hb, g/L) divided by RDW (%). Patients were categorized into three groups based on HRR tertiles. Multivariable Cox proportional hazards models were constructed to quantify the independent association between HRR and 1-year all-cause mortality after adjustment for confounders. Restricted cubic splines (RCS) were further used to analyze the dose-response relationship between HRR and mortality risk. Kaplan-Meier survival analysis revealed significant differences in survival across HRR groups. Furthermore, sensitivity analyses and subgroup analyses were performed to validate the study findings. Results A total of 1,209 patients were included, of whom 54.6% were male (n = 660). Cox proportional hazards model analysis showed that after adjusting for potential confounding factors, each 1-unit increase in HRR was associated with a 21% reduction in 1-year all-cause mortality risk (HR = 0.79, 95% CI 0.70–0.89, P < 0.001). When stratified by HRR tertiles, the high-HRR group (HRR > 8.43) exhibited a significantly lower risk of 1-year mortality compared with the low-HRR group (HRR < 6.69) (HR = 0.43, 95% CI: 0.27–0.71, P = 0.001). Kaplan-Meier survival analysis revealed that patients with higher HRR had lower mortality rates (log-rank P < 0.001). RCS regression demonstrated a continuous linear relationship between higher HRR values and reduced mortality risk. No significant interactions were observed in the subgroup analyses. Conclusion The study demonstrates a significant association between lower HRR and increased 1-year mortality risk in TAVR patients. This simple and readily available indicator may serve as an adjunctive risk marker pending prospective validation. Clinical trial number Not applicable.